How to make perfect strawberry jam

In my memory, the hazy golden summers of the 80s smell of cut grass and taste of strawberries – strawberry picking, strawberry teas, sickly strawberry splits; softer and sweeter than the glossily handsome fruit I buy today, and forever teetering on that fine line between ripe and rotten. Strawberry jam, with its mushy, slightly leathery fruit and syrupy flavour, always takes me back to those sunburnt days, when rollerskates were supercool, and summer fruit came with a lurid scoop of Gino Ginelli rather than a sprinkling of black pepper.

In jam form, of course, the strawberry is the perfect compliment to those other stalwarts of the rose-tinted picnic rug of summers past, the scone and the Victoria sponge. And, like both those things, the homemade version is infinitely better than anything you can buy in the shops; less sugary, more fruity, and above all, sticky with good old-fashioned nostalgia – and what could be more British than that?

Which set are you part of?

The principle problem to overcome when making strawberry jam is their lack of pectin, which, according to Darina Allen's Ballymaloe Cookery Course, is a "mucilaginous substance" (tasty) that rather handily, acts a setting agent. The more acidic the fruit, the more pectin it is likely to contain – so the intense sweetness of the fully ripe strawberry counts against it here.

Fear not: there are three ways to up the pectin quota: firstly, with the juice of a more acidic fruit, such as lemon or currants, secondly by using jam sugar (which includes pectin), and thirdly by adding some in liquid form to ordinary sugar (some sticklers regard the use of artificial pectin as cheating, but with strawberries, I suspect they're making a rod for their own backs; it just provides extra reassurance that you're going to be able to spoon, rather than pour, your breakfast condiment).

Jamie Oliver, however, has no such qualms. He uses 500g jam sugar to each kilo of fruit in his strawberry jam – but without a spritz of lemon juice, the results are overpoweringly sweet, even by jam standards, and the set is quite loose – it slides all over my scone. His nan, seen tucking in at the end of the video, may approve, but it reminds me slightly of the sickly pink syrup that adorned the 99s of childhood: not the kind of nostalgia I'm after.

Nick Sandler and Johnny Acton go down the opposite route in Preserved, using ordinary white sugar and lemon juice (2 lemons to 3kg of fruit). The set is much better, and the jam has a richer flavour – as Pam Corbin, aka Pam the Jam points out in the River Cottage Preserves handbook, the acidity helps the jam "come alive".

The more pragmatic Nigella Lawson hedges her bets by using both preserving sugar (which contains less pectin than jam sugar, and thus is more generally deployed for sourer fruits such as blackcurrants) and lemon juice, on the basis that "the lemon provides enough pectin to make the jam set and the larger crystals of the preserving sugar make for a clearer, more jewel-like, jam." The domestic goddess certainly makes a beautiful preserve – with the sun shining through it, I could even be moved to the adjective "ruby", but despite me boiling it for the full 8 minutes directed, the set is distinctly liquid. One to keep in the fridge.

Ballymaloe take a more seasonal approach to things by using redcurrant rather than lemon juice, made by simmering a couple of punnets of the astringent little fruits with water, and then pushing them through a sieve. The jam, made with ordinary granulated sugar, really does have a lovely flavour, but again, the set is soft – not as soft as Nigella's, but more than is convenient for spreading on a scone.

Although I've no doubt that, with the perfect fruit and a lot of patience, a great jam can be achieved without special sugar, I think strawberries are temperamental enough to mean that a combination of acid and jam sugar is wise. Why spoil a strawberry for the sake of a principle?

A labour of love

Of course, the cooking time may also affect the set – and that varies wildly among recipes, from 4 minutes from Jamie to a rather more dedicated 3 days from Thane Prince. The recipe in her book Jams and Chutneys is credited to her friend Sue, and requires the cook to macerate the fruit, sugar and lemon juice for 24 hours, before bringing the mixture to the boil and simmering it gently for 5 minutes. It's then left to mature in the pan for a couple of days, before being reheated and cooked until set to the cook's satisfaction – "the jam will always be quite soft, so I boil it until it thickens to my liking" Thane says. (Incidentally, Christine Ferber, la fée des confitures or jam fairy of Alsace, uses a similar method – and her jam is swooned over by the likes of Alain Ducasse.)

I'm expecting something spectacular, but although the results are certainly rich in flavour, the dark jam isn't as bright and fresh as, say, the Ballymaloe version: it's a sophisticated, grown-up take on what, in my opinion, should be a simpler pleasure. Although the hour's simmering advocated by the Preserved boys does help thicken the jam, it also leaves it with a slightly caramelised flavour – the 15 minutes suggested by Ballymaloe seems perfect: long enough to set the jam without robbing it of all freshness.

Texture

Ballymaloe and Jamie Oliver both advocate mashing most of the strawberries, leaving only a few whole ones for interest's sake. Johnny and Nick leave the smaller berries whole, and chop the larger ones up, and Nigella doesn't bother to do anything to them, although she allows you could cut them up "if you like". I find too many large berries make the finished jam more like a compote, but scooping out the occasional baby is a real treat sadly lacking in most commercially-produced examples.

Flavourings

Jamie sticks vanilla seeds in his jam, which only adds to its slightly sickly character, and Nigella pops in a teaspoon of balsamic vinegar for that authentic mid-nineties feel – although balsamic goes well with strawberries, I prefer my strawberry jam to have a fresher flavour. The redcurrants used by Ballymaloe adds a subtle bittersweetness which works really well with the sweet strawberries, and gives the jam a lovely scarlet colour too, but the zingy tartness of the lemons win the day for me – as Pam the Jam so wisely observed, it really lifts the flavour.

Perfect strawberry jam

Great strawberry jam is surprisingly quick and easy to make especially if a spurt of enthusiasm at the pick-your-own has left you with a glut, or you spot some overripe fruit going cheap at the market – it's the flavour of summer all year round. All you need are good berries, and a little patience. And, of course, a good scone recipe.

Makes 4 x 200ml jars

2kg small ripe strawberries1.7kg jam sugarJuice of 2 lemons

1. Hull the strawberries and discard any rotten ones. Set aside about 10 of the smallest berries, and then mash the rest up into a rough pulp. Put into a wide, thick-bottomed pan, add the sugar and the lemon juice, and bring to the boil. Add the remaining strawberries to the pan, and put a saucer in the freezer.

2. Boil the jam for about 15 minutes, stirring regularly checking the setting point every minute or so during the last 5 minutes. To do this, take the cold saucer out of the freezer, put a little jam on it, and put it back in to cool for a minute. If it wrinkles when you push it with your finger, then it's done. Strawberry jam is unlikely to set very solid though, so don't expect the same results as you would with a marmalade.

3. Take off the heat and skim off the pink scum. Pour into sterilised jars and cover with a disc of waxed paper, seal and store.

How do you deploy strawberry jam, and what else do the gardeners among you do with gluts of summer fruit?